1. Field of the Invention
The present invention relates to ventilation members.
2. Description of Related Art
Conventionally, in automotive electrical/electronic components such as automotive lamps and ECUs (electronic control units), OA (office automation) equipment, household electrical appliances, medical equipment, etc., openings are formed in housings containing electronic components, control boards, etc. to reduce pressure fluctuations due to temperature changes in the housings or to ventilate the interior of the housings, and ventilation members are attached to the openings. These ventilation members not only ensure ventilation between the interior and exterior of the housings but also prevent foreign substances such as dust and water from entering the housings. JP 2004-047425 A discloses an example of such a ventilation member. FIG. 4 shows a ventilation member disclosed in JP 2004-047425 A.
A ventilation member 110 includes a support 104, an air-permeable membrane 102 disposed on the support 104, a cover member 106 covering the air-permeable membrane 102, and a sealing member 108 mounted in a gap between the support 104 and a housing 120. The ventilation member 110 is fixed to an opening 121 of the housing 120 via the sealing member 108. Leg portions 112 of the support 104 are engaged with the opening 121 to prevent detachment of the ventilation member 110 from the housing 120. The sealing member 108 is a resin O-ring mounted around the opening 121 and in the gap between the support 104 and the housing 120.